Write the formula for the coefficient of performance of a heat pump.

(N/A) The coefficient of performance ($\beta$ or $COP$) of a heat pump is defined as the ratio of the heat delivered to the hot reservoir $(Q_H)$ to the work done on the system $(W)$.
Mathematically, it is expressed as:
$\beta = \frac{Q_H}{W}$
Where:
$Q_H$ is the heat delivered to the hot reservoir.
$W$ is the work input.
Since $W = Q_H - Q_L$, the formula can also be written in terms of temperatures as:
$\beta = \frac{T_H}{T_H - T_L}$
where $T_H$ is the temperature of the hot reservoir and $T_L$ is the temperature of the cold reservoir.